TW202020076A - Abrasion-resistant coatings for thermal interfaces - Google Patents

Abstract

A system having a removable electronic component employs an abrasion-resistant thermally conductive film as a thermal interface between the removable electronic component and a heat sink. The abrasion-resistant film reduces thermal impedance between the removable electronic component and the heat sink when the removable electronic component is repeatedly installed and removed from a chamber in a host device. The abrasion-resistant film includes a polymer formed from a silicon-containing resin and an inorganic particulate filler, the film may also be interlocked with a corrosion protection layer at the heat sink. A method of forming a heat sink is provided that minimizes increases in thermal impedance.

Description

Wear-resistant coating for thermal interface

The present invention relates to a thermally conductive film as a thermal interface between a heat generating device and a heat sink. The present invention is more specifically directed to a wear-resistant thermally conductive film that reduces the thermal impedance between the heating device and the heat sink to allow repeated installation and removal of the heating device.

Electronic systems are increasingly dependent on faster speeds and greater capabilities in smaller packages. In addition, electronic systems continue to use increasingly complex arrays of electronic devices, including modular arrays that can operate with various and replaceable components. Examples of replaceable components include optical transceivers, such as C form factor pluggable (CFP) optical transceivers and small form factor pluggable (SFP) optical transceivers, which can be installed in modular systems and/or self-mode Disassemble the system. Such optical transceivers are "pluggable" because they can be plugged into and removed from a host device or system without removing power from the host device or system. Pluggable transceivers are usually received in chambers or ports defined by the respective frames of the host system.

To prevent heat accumulation in the pluggable electronic components, heat dissipation devices can be used at and/or around the receiving chamber to assist in dissipating the generated heat away from the pluggable electronic components. In a typical embodiment, the heat dissipation device contacts the pluggable electronic component when installed in the chamber, so that the self-pluggable electronic component can dissipate heat in a conductive manner. The efficiency of heat conduction from the pluggable electronic component to the heat dissipation device is largely limited by the thermal impedance of the interface between the pluggable electronic component and the heat dissipation device. Generally, non-contact in some interfaces may hinder heat transfer, so that heat transfer by conduction is limited to part of the contact area, where pluggable electronic components are in contact with various surfaces of the heat dissipation device. Usually, the contact surface is metal non-uniform. The uneven surface combined with surface rigidity prevents extensive physical contact between the surfaces.

One way to reduce the thermal resistance at the interface between metal surfaces is to coat at least one of the metal surfaces with a flexible or conformable thermal interface material, such as paste, gel, film, or the like. Although these conformable thermal interface materials are effectively used in static applications of pluggable electronic components and associated heat dissipation devices, they cannot withstand the abrasion forces induced in dynamic environments such as pluggable electronic components , Such as a pluggable electronic component in which the pluggable electronic component repeatedly slides into and out of the chamber in abrasive contact with the heat dissipation device. Therefore, due to the repeated installation and removal of pluggable electronic components, these suitable thermal interface materials tend to disintegrate within a period of time. The degradation of the thermal interface material results in an increase in the thermal impedance of the heat transferred from the pluggable electronic component to the heat dissipation device.

Therefore, there is a need for a thermal interface material that is applied to the interface between the pluggable electronic component and the heat dissipation device, the interface material is both adequately shaped to reduce the thermal resistance of the interface, and sufficiently wear-resistant to withstand Repeated installation and disassembly of the pluggable electronic components from the host device in contact with the heat dissipation device. Such abrasion resistance is expected to include both the cohesion of the thermal interface material and the adhesion of the thermal interface material to various surfaces, such as the surfaces of heat dissipation devices.

This document discloses a system that includes a frame defining a chamber, a heat sink, and removable electronic components that are removably inserted into the chamber to make thermal contact with the heat transfer area of the heat sink. The heat sink includes a metal substrate having a first surface and a second surface defining a thickness therebetween, the metal substrate has a substrate thermal impedance; a thermally conductive film disposed on the first surface or the second surface defining the heat transfer area On at least a portion of at least one of the at least one, the thermally conductive film includes (1) a polymer formed of silicone-containing resin and (2) an inorganic particulate filler. The initial thermal resistance across the thickness through the heat transfer area is defined before the Taber wear test, and the thermal resistance through the heat transfer area is defined across the thickness of the metal substrate when the Taber wear test is completed, wherein The abrasion thermal resistance is greater than the initial thermal resistance by about 50% or more.

Another embodiment discloses a system including: a host device including a frame defining a chamber; a detachable module that generates heat transferred to the first surface of the module, the module passes through the chamber to Removably installed in the host device; and a heat sink associated with the frame to dissipate heat from the first surface. The heat sink includes a second surface on which a thermally conductive film is applied to define the heat transfer area of the heat sink, and wherein a thermally conductive film is applied to define the heat dissipation on at least a portion of the first surface or the second surface The heat transfer area of the device, and wherein when the module is installed in the device to allow heat to be received by the first surface, the thermally conductive film is in direct contact with the first surface or the second surface. The system exhibits an initial thermal resistance through the heat transfer area before the Taber abrasion test, and exhibits abrasion thermal resistance through the heat transfer area after completing the Taber abrasion test, the abrasion thermal resistance is greater than the initial thermal resistance by no more than about 50%.

In yet another embodiment, a system is disclosed, wherein the system includes: a host device including a frame defining a cavity; a removable module that generates heat transmitted to the first surface of the module, the module Removably installed in the host device via the chamber; a heat sink, which is associated with the frame to dissipate heat from the first surface. The heat sink includes a heat sink including a second surface, and a thermally conductive film applied to the first surface or the second surface. When the module is installed in the device to allow heat to be received by the first surface, the thermally conductive film directly contacts the first surface, the second surface includes a corrosion protection layer, and the thermally conductive film includes protection from the corrosion Silicon-containing polymer with interlocking layers.

In yet another embodiment, a method for forming a heat sink is provided, which includes: providing a metal substrate having a first surface, treating the first surface with a conversion agent to form a corrosion protection layer, and preparing a silicon-containing resin and an inorganic The particulate filler precursor, coating the precursor onto the corrosion protection layer, and curing in situ to polymerize the precursor. The silicon-containing polymer formed by the resin interlocks with the corrosion protection layer.

The invention relates to a detachable electronic component suitable for interacting with a host device when installed at the host device. The detachable electronic component is installed in and detached from the host device through sliding engagement and disengagement with the heat sink. The heat sink is usually positioned in the cavity/container of the host device so that the removable electronic component is installed and placed in thermal contact with the heat sink. The thermal contact is established by the thermal interface between the detachable electronic component and the heat sink. The thermal interface is at least partially filled by the thermal interface member of the present invention. The thermal interface member may preferably be a wear-resistant and viscous body in the form of a film or coating. The thermal interface member can be adhered to a portion that can be a heat sink or thermally coupled to the heat transfer surface of the heat sink. The removable electronic component is installed in the cavity/container of the host device and the heat transfer surface of the removable electronic component is placed in thermal contact with the thermal interface body, which is itself connected to the heat sink.

As used herein, the term "host device" is intended to mean a computer or computing device, network device, signal transmitter, signal receiver, switch, data storage device, subsystem, printed circuit board, integrated circuit, microprocessor Or similar devices.

1 and 2 depict schematic cross-sectional views of an example system 10 of the present invention. The removable module 12 illustrated as being installed into the chamber 14 of the host device 16 along the direction arrow 13 is shown in FIG. 1. FIG. 2 illustrates the system 10 with the removable module 12 installed at the host device 16. The removable module 12 may have a first surface 12a to which heat generated by the removable module 12 is transferred. It is expected that the heat generated by the removable module 12 can be transferred to the portion of the removable module 12 other than the first surface 12a, but for the purpose of this specification, the heat dissipation is directed to the host device via the first surface 12a 16. The removable module 12 may be, for example, a pluggable optical transceiver.

The system 10 includes a heat sink 20 for dissipating heat from the removable module 12 via the first surface 12a. The heat sink 20 may be associated with the frame 15 of the host device 16. The heat sink 20 is usually composed of a high thermal conductivity material (such as metal, metal alloy, and the like), and may include one or more heat dissipation devices, which effectively dissipate the heat generated by the removable module 12. In the embodiment illustrated in FIG. 1, the heat sink 20 may include a plate portion 22 and fins 24 extending from the plate portion 22 and thermally coupled to the plate portion 22. The heat sink 24 provides an increased surface area to enhance heat transfer to a cooling medium (not shown) in contact with the heat sink 24 (such as ambient air). The heat sink 20 may be made of various thermally conductive materials, and examples of such thermally conductive materials include but are not limited to aluminum and copper. The plate portion 22 of the heat sink 20 includes a heat receiving surface 26 for receiving heat from the removable module 12.

The thermally conductive film 30 is preferably applied to the heat receiving surface 26 to define the heat transfer area “A”, in which the heat from the removable module 12 is most efficiently transferred to the heat sink 20 via the thermally conductive film 30. This heat transfer area "A" reduces the thermal resistance of the heat sink 20. The heat transfer area "A" may be of any size, preferably about 0.5-1.5 cm ² , more preferably about 1.0 cm ² .

A thickness "T" is defined between the heat receiving surface 26 and the heat dissipating surface 28. As shown in FIG. 1, when the detachable module 12 is installed as illustrated in FIG. 2, the heat sink 20 and the thermally conductive film 30 may be mounted to the frame 15 in a manner that causes contact with the first surface 12 a of the module 12. This contact allows the heat sink 20 to receive the heat generated by the removable module 12 and dissipate the heat in a suitable manner.

When the module 12 is installed in the cavity 14 of the host device 16, the thermally conductive film 30 is thermally coupled to the first surface 12a of the module 12, preferably in direct contact with the first surface. Therefore, the thermal conductive film 30 is located at the thermal interface between the module 12 and the heat sink 20. In this way, the module 12 is thermally coupled to the heat sink 20 via the thermally conductive film 30.

The thermally conductive film 30 is conformable, deformable and/or flexible to fill the gap between the first surface 12a of the removable module 12 and the heat receiving surface 26. Therefore, the thermally conductive film 30 functions to fill the voids, otherwise these voids will present a considerable resistance to the heat transfer between the first surface 12a of the removable module 12 and the heat receiving surface 26 of the heat sink 20. Therefore, the thermally conductive film 30 forms a part of the heat transfer path between the detachable module 12 and the heat dissipation surface 28 / fin 24. A heat transfer path is established, which transfers heat from the first surface 12a via conduction, through the thermally conductive film 30, and to the heat receiving surface 26.

In order to effectively fill the gap at the interface between the removable module 12 and the heat sink 20, the thermally conductive film 30 preferably exhibits a relatively low elastic modulus/Young's modulus and a relatively low flexural modulus. In some embodiments, the thermally conductive film 30 has an elastic modulus/Young's modulus of less than about 10 MPa and more preferably less than about 1 MPa, wherein the rebound after compression according to ASWTM-D395 is greater than about 95%. The flexibility/deformability can be adjusted by changing the shape or thickness of the thermal conductive film 30. In some particularly suitable embodiments, the thermally conductive film 30 is applied at a substantially uniform thickness ("T _f ") of less than about 75 μm (eg, about 10-50 μm).

The thermally conductive film 30 is thermally conductive, conformable and wear-resistant, so that the thermally conductive film 30 is durable in applications similar to those described above, in which the removable module 12 is repeatedly installed and removed from the host device The chamber 14 of 16 is disassembled. The removable module 12 is usually installed and reinstalled with sliding contact with the thermally conductive film 30. Therefore, damage to the thermal conductive film 30 due to such repeated installation and removal can significantly increase the thermal resistance at the interface between the first surface 12a of the module 12 and the heat receiving surface 26 of the heat sink 20. Therefore, it is important that the thermally conductive film 30 is also resistant to wear due to the sliding contact between the module 12 and the thermally conductive film 30. In some embodiments, the thermally conductive film 30 may exhibit a thermal conductivity of at least about 0.1 W/m•K and more preferably at least about 0.5 W/m•K, where the thermal conductivity is measured by the thickness T _{f of the} thermally conductive film 30.

The thermally conductive film 30 is preferably formed of one or more polymer molding resins and one or more inorganic particulate fillers. In some embodiments, the polymer molding resin is a silicon-containing thermosetting resin. Exemplary thermosetting resin compositions intended for the thermally conductive film 30 include epoxy resins, acrylates, and polyurethanes. Other examples of polymer molding resins suitable for the thermal connective film 30 of the present invention are described in US Patent Nos. 5,028,984 and 3,908,040, which are incorporated herein by reference in their entirety.

In an exemplary embodiment, the cross-linked polymer network is formed of two-part platinum-catalyzed, addition-cured polysiloxane polymer, which is used in conjunction with methylhydrogensiloxane-dimethylsiloxane, trimethylsilane Oxygen-terminated copolymer reacts with vinyl-terminated polydimethylsiloxane.

Inorganic particulate fillers are also included in the thermally conductive film 30. In some embodiments, the inorganic particulate filler is selected from alumina, diamond, clay, aluminosilicate, aluminum nitride, boron nitride, alumina, aluminum nitride, magnesium oxide, zinc oxide, silicon carbide, silicon dioxide , Beryllium oxide, antimony oxide and combinations thereof. In a particularly suitable embodiment, the inorganic particulate filler is aluminum nitride. In another embodiment, the filler is selected from the group consisting of carbon nanotubes, graphene, fullerene, and graphite.

The inorganic particulate filler can be added to the polymer molding resin at a concentration of less than about 300 parts per hundred parts resin (phr) and more preferably less than about 150 phr. It has been surprisingly determined that an inorganic particulate filler concentration of less than or equal to 50 phr provides the benefit of enhancing the wear resistance of the thermally conductive film 30. As described in more detail below, reducing loading of the inorganic particulate filler to the thermally conductive film 30 can reduce the degradation of the thermally conductive film after the wear test, and thus minimize the increase in thermal impedance at the heat transfer area "A" after the wear test . The lower particle filler concentration of Xianxin will reduce the interference with the adhesion of the polymer matrix to the metal substrate. Therefore, a lower concentration of particulate filler may permit "more tough" cross-linked polymers that exhibit enhanced wear resistance. Although less inorganic filler is present in the thermally conductive film 30, such enhanced wear resistance maintains a lower thermal resistance after the wear test. The maintenance of abrasion resistance and continuity of the polymer matrix is surprisingly better in terms of maintaining low thermal resistance, such as a lower film, which can itself be more thermally conductive due to higher inorganic particulate filler concentration content.

In some embodiments, the maximum particle size of the inorganic particulate filler may be less than about 50 μm and more preferably less than about 25 μm. In an exemplary embodiment, the average particle size of the inorganic particulate filler may be between about 1-5 μm and more preferably about 3 μm.

The heat sink including the thermally conductive film 30 may be formed by applying the precursor to the heat receiving surface 26 of the plate portion 22 and curing the precursor in situ at the heat receiving surface 26. In a suitable embodiment, the plate portion 22 includes a metal substrate having a first surface of the aluminum or copper plate portion 22 (such as the heat receiving surface 26). The invention covers other metals or metal alloys that include a metal coating at the heat receiving surface 26. In some embodiments, the first surface of the metal substrate may be treated with a conversion agent to form a corrosion protection layer. The conversion agent may be at least one of hexavalent chromium, trivalent chromium, tin, titanium oxide, magnesium oxide, chromium-free Alodine and zinc.

The precursor for applying to the converted first surface of the metal substrate may include a silicon-containing resin and an inorganic particulate filler, wherein the silicon-containing resin may be a polymer molding resin. Such precursors may be applied to the corrosion protection layer with a thickness of less than 75 μm, and preferably between 10-50 μm. The precursor can be applied to the corrosion protection layer via screen printing, slit coating, dip coating, selective printing, curtain coating, slot die application, or other suitable coating techniques. The precursor material can be liquid, paste, gel, grease or other forms called pre-cured state. In one embodiment, the precursor may be a solution dissolved in one or more solvents. The coated precursor can be cured in situ by an appropriate curing mechanism to polymerize the precursor, wherein the silicon-containing polymer formed by the resin is interlocked with the corrosion protection layer. The curing mechanisms intended for use herein include, but are not limited to, ultraviolet radiation, thermal radiation, sonic treatment, chemical curing, and the like.

The term "interlock" is intended herein to mean the bonding between the silicon-containing polymer and the corrosion protection layer, which at least partly involves, for example, "Chemical Adhesion of Silicone Elastomers on Primed Metal Surfaces: A Comprehensive Survey of Open and Patent Literatures" , Progress in Organic Coatings , Loic Picard et al., mechanical interlock described in pages 80-141 of Volume 80 (2015), the content of this patent is incorporated herein by reference. Examples of such bonding couple polysiloxane elastomers to primed metal surfaces.

Referring now to the flowchart of FIG. 3, an exemplary method for forming the heat sink 20 incorporating the thermally conductive film 30 will be described. To provide the required wear resistance, the thermally conductive film exhibits a high level of cohesion and a high level of adhesion to the metal heat receiving surface 26. To assist such adhesion, the heat receiving surface 26 can be treated for enhanced bonding with the polymer film. The metal surface can be passivated to form a corrosion protection layer, which is also used to interlock with the polymer of the thermally conductive film. Various metal surface treatments can be used to passivate metal surfaces, including (but not limited to) anodization, chromate conversion, tin plating, and zinc plating. An example of a suitable metal surface treatment is chromate conversion coating using trivalent (type 1) or hexavalent (type 2) chromium, which is commercially available under the trademarks of Henkel Corporation, Madison Heights, Bonderite of MI, or Alodine .

Other suitable metal surface treatments include those available under the trade name EC ² from Henkel Corporation and electronic ceramic coating as described in US Patent Application Publication No. 2017/0121841, and US Patent Nos. 6,946,401; 6,361,833; The metal surface treatments described in 4,162,947 and 3,434,943 and U.S. Patent Application Publication No. 2010/0038254, the respective contents of which are incorporated herein in their entirety.

The treated metal radiator is then immersed in a solvent such as isopropyl alcohol, acetone, alkanes or water for ultrasonic treatment for 2-10 minutes. Remove the metal radiator from the ultrasonic treatment bath and dry it with an ionizing air gun (such as the "Top Gun Static Elimination Gun" purchased from Simco-Ion) to reduce or eliminate the static charge from the metal surface and particle.

After the ionization air drying step, the metal radiator is treated with ultraviolet radiation and ozone to clean solvent residues, silicone oil or flux.

A precursor with a silicone-containing resin and inorganic particulate filler is prepared and applied to the corrosion protection layer prepared as described above. The precursor can be applied to the corrosion protection layer on the passivated metal surface by screen printing or other low-volume application procedures such as slit coating, dip coating, or selective printing. The coated radiator is then baked in an oven at 25-200°C for 1-240 minutes to cure/polymerize the precursor in situ.

The thermally conductive film composition according to the present invention may further include one or more flow additives, adhesion promoters, rheology modifiers, toughening agents, fluxes, reaction rate control agents, and the like, and combinations thereof, as the case may be. An example of a reaction rate modifier is tetravinyltetramethylcyclotetrasiloxane. Examples or surface coupling agents/adhesion promoters used to improve the adhesion of the film to the metal heat sink include epoxy-functional trimethoxysilane, vinyl-functional trimethoxysilane, and methacrylate-functional trimethoxysilane. Titanium (iv) butoxide can be used to catalyze the condensation of the silane coupling agent with the target substrate. Examples of toughening agents may include fumed silica treated with hexamethyldisilazane. Film composition

實例材料 2 ( 對於銅金屬基板 )

耐磨性測試 The following composition is intended to be exemplary only, and indicates certain components that can be included in the film composition of the present invention. Example material 1 ( for aluminum metal substrate )

Example material 2 ( for copper metal substrate )

Wear resistance test

The heat resistance of the heat sink coated with the thermal conductive film of the present invention was tested. The test method used in this article (called the "Tarbo Abrasion Test") includes concepts from the ASTM standards of G133, F732, F2025, F2496, and D4060 in order to analyze the resistance of the coating to abrasion. Because the success of the film of the present invention depends on the resistance to abrasion during repeated installation and disassembly using the host device, the Taber Abrasion Test attempts to quantitatively analyze the performance of the film. Similar to the methods outlined in ASTM F732 and F2496, the quantitative measurement of abrasion resistance is the volume percent loss of the coated film during the wear test. The volume loss can be determined gravimetrically by calculating the mass loss after wear (similar to ASTM G133 and D4060). The original and lost quality of the coated film allows comparison of coatings with different densities.

Reciprocating grinders are available from Taber Industries under model 5900. The Taber reciprocating triturated with from 3M Company of Scotch-Brite ^® Universal purge fitting pad as a polishing surface. Use an analytical balance capable of measuring the closest to 0.1 mg to determine the quality of the loaded film and the mass loss after the wear test. program

The film quality is determined by finding the difference between the mass of the coated substrate and the tare weight of the coated metal substrate. Place the sample to be ground in the fixture on the reciprocating grinder and hold it firmly in place. Then, a polishing pad with an area of 1 inch ² is placed in contact with the film, and a force of 5N is applied. Engage the reciprocating grinder and linearly reciprocate the required number of cycles at a rate of 60 revolutions per minute. The reciprocating "cycle" used in this article includes two passes across the surface of the film, each of which covers an 80 mm stroke length. Each sample included a film of Example Material 1 or Example Material 2, which was applied to a 1 inch by 4 inch aluminum lap under the procedure described with reference to FIG. 3.

After completing the reciprocating cycle, remove the sample from the fixture and remove any loose material/debris with compressed air at 35 psi and wipe it clean with a lint-free cloth immersed in isopropyl alcohol. The ground sample was then dried and weighed to determine the mass loss of the film. When exposed to 400 cycles of a reciprocating grinder, any film quality loss of more than 20% is considered a film durability failure. The samples were weighed after each of 50, 100, 200 and 400 passes. result

Experiments were performed on aluminum substrate samples coated with Example Material 1 but with different particulate filler concentrations using Taber Abrasion Test Technology. Figures 5-8 illustrate the results of the Taber abrasion test on samples incorporating 25, 50, 150, or 250 phr aluminum nitride filler. Figures 5-8 illustrate the unexpected benefits of abrasion resistance of films containing less than or equal to 50 phr inorganic filler. The results are especially illustrative in the "relative mass loss" bar graphs, which illustrate the relative mass loss during the Taber abrasion test, not just the absolute mass loss, which can be Quality to achieve. Thermal performance test

The thermal resistance before and after the Taber abrasion test was also compared, and the abrasion resistance and durability were tested by thermal performance. According to the test method MET BASA#MET-5.4-01-1900-Test 2.1, the thermal resistance was measured on an area of about 1.0 cm ² . After the Taber abrasion test, a 50% increase in thermal resistance is considered a failure. Examples

After the Taber abrasion test, the following samples were tested for both abrasion resistance and thermal performance:

10: System 12: Removable module 12a: First surface 13: Direction arrow 14: Chamber 15: Frame 16: Host device 20: Heat sink 22: Plate part 24: Heat sink 26: Heat receiving surface 28: Heat Dissipative surface 30: thermally conductive film T: thickness T _f : uniform thickness A: heat transfer area

FIG. 1 depicts a schematic cross-sectional view of the system of the present invention, wherein the detachable module is installed in the host device.

FIG. 2 depicts a schematic cross-sectional view of the system of the present invention, wherein the detachable module is installed in the host device.

Figure 3 depicts a flow chart of the steps of coating a metal substrate with a thermally conductive film.

FIG. 4 is a graph illustrating the absolute quality loss of thin films from each metal substrate after the Taber abrasion test.

Figure 5 is a graph illustrating the relative mass loss of thin films from each metal substrate after the Taber abrasion test.

FIG. 6 is a graph illustrating the absolute quality loss of thin films from each metal substrate after the Taber abrasion test.

7 is a graph illustrating the relative quality loss of thin films from each metal substrate after the Taber abrasion test.

10: System

12: Removable module

12a: first surface

13: direction arrow

14: chamber

15: Frame

16: Host device

20: radiator

22: Board section

24: Heat sink

26: heat receiving surface

30: Thermally conductive film

Claims (25)

A system that includes: a. Frame, which defines the chamber; and b. Radiator, which contains: A metal substrate having a first surface and a second surface defining a thickness therebetween, the metal substrate has a substrate thermal resistance; A thermally conductive film disposed on at least a portion of at least one of the first surface or the second surface that defines the heat transfer area, the thermally conductive film includes (1) a polymer formed of silicon-containing resin and (2) inorganic Particulate filler, Where the initial thermal resistance across the thickness through the heat transfer area is defined before the Taber wear test, and the wear thermal resistance across the thickness of the metal substrate through the heat transfer area is defined when the Taber wear test is completed, Where the thermal resistance of the wear is greater than the initial thermal resistance by more than 50%; and An electronic component is detachably inserted into the chamber for thermal contact with the heat transfer area of the heat sink. The system of claim 1, wherein each of the initial thermal impedance and the abrasion thermal impedance is less than the substrate thermal impedance. The system of claim 1, wherein the abrasion thermal impedance is less than about 1.8°C/W. The system of claim 1, wherein the inorganic particulate filler is present in the film at a concentration of less than or equal to about 50 phr. The system of claim 4, wherein the maximum particle size of the inorganic particulate filler is less than about 50 μm. The system of claim 5, wherein the average particle size of the inorganic particulate filler is about 3 μm. The system of claim 4, wherein the inorganic particulate filler is selected from the group consisting of alumina, zinc oxide, magnesium oxide, aluminum nitride, boron nitride, silicon dioxide, diamond, clay, aluminosilicate, and combinations thereof. The system of claim 1, wherein the thickness of the substrate is between about 10-100 μm. The system of claim 8, wherein the thickness of the thermally conductive film is less than about 25 μm. A system that includes: The host device, which includes a frame defining the chamber; A detachable module, which generates heat transferred to the first surface of the module, the module can be detachably installed in the host device through the chamber; A heat sink associated with the frame to dissipate heat from the first surface, wherein the heat sink includes a second surface; Applying a thermally conductive film to define the heat transfer area of the heat sink on at least a portion of the first surface or the second surface, and wherein when the module is installed in the device to permit the heat to be received by the first surface, The thermally conductive film is in direct contact with the first surface or the second surface, Wherein the system exhibits an initial thermal resistance through the heat transfer area before the Taber abrasion test, and exhibits an abrasion thermal resistance through the heat transfer area when the Taber abrasion test is completed, the abrasion thermal resistance is greater than the initial thermal resistance and does not exceed About 50%. The system of claim 10, wherein the thermally conductive film reduces the thermal impedance of the contact area between the heat sink and the first surface. The system of claim 11, wherein the thermally conductive film includes a polymer formed of silicone-containing resin and inorganic particulate filler. The system of claim 12, wherein the inorganic particulate filler is present in the thermally conductive film at a concentration of less than or equal to about 50 phr. The system of claim 13, wherein the maximum particle size of the inorganic particulate filler is less than about 50 μm. The system of claim 10, wherein the thickness of the thermally conductive film is less than about 25 μm. A system that includes: The host device, which includes a frame defining the chamber; A detachable module, which generates heat transferred to the first surface of the module, and the module is detachably installed in the host device through the chamber; A heat sink associated with the frame to dissipate heat from the first surface, wherein the heat sink includes a second surface, and a thermally conductive film is applied to the first surface or the second surface, and wherein the module When installed in the device to allow the heat to be received by the first surface, the thermally conductive film directly contacts the first surface, the second surface includes a corrosion protection layer, and the thermally conductive film includes an interlock with the corrosion protection layer Contains silicon polymer. The system of claim 16, wherein the corrosion protection layer includes at least one of a porous oxide layer, silane, and methacrylate. The system of claim 17, wherein the thermally conductive film includes inorganic particulate filler, and the silicon-containing polymer is formed of silicon-containing resin. The system of claim 18, wherein the inorganic particulate filler is present in the film at a concentration of less than or equal to about 50 phr. The system of claim 19, wherein the thermally conductive film reduces the thermal impedance of the contact area between the heat sink and the first surface. A method for forming a heat sink, which includes: Provide a metal substrate with a first surface; Treat the first surface with a conversion agent to form a corrosion protection layer; Preparation of precursors with silicone resin and inorganic particulate filler; Applying the precursor onto the corrosion protection layer and curing in situ to polymerize the precursor, The silicon-containing polymer formed by the resin interlocks with the corrosion protection layer. The method of claim 21, wherein the conversion agent includes at least one of hexavalent chromium, trivalent chromium, tin, titanium oxide, magnesium oxide, chromium-free Alodine and zinc. The method of claim 21, which includes coating the precursor onto the corrosion protection layer by screen printing, slit coating, dip coating, selective printing, or a combination thereof. The method of claim 22, wherein the thickness of the silicon-containing polymer is less than about 25 μm. The method of claim 21, wherein the inorganic particulate filler is present at a concentration of less than or equal to 50 phr.

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